[M10] General Discussion on Rules Changes

[Pinder]

Because you still have to assign damage to creatures that won't die from damage.

To be fair, we've already had to do this. A green creature with trample won't assign all of its damage to the player when a creature with Pro:Green blocks it, the attacker still has to assign lethal damage (again, not the same thing as "the damage that actually kills it") to the blocking creature.

It's just that, now, we have to "trample" through each blocker, as well.

And if they'll die for some other reason, like the Pyroclasm in your hand or a Graveyard-trigger ability on your creature like Bogardan Firefiend? Nope, still doesn't matter.

If you're looking to capitalize on a graveyard trigger or something, you could always order it so that the creature you're intending on targeting with your Firefiend comes last, and assign the combat damage through the rest of them. The attacking player gets to decide the order they have to go through the blockers in.

But your Pyroclasm example stands. And I still agree that we should be able to divvy up damage however we want.